Delivery system for loosely coherent sheets



Nov. 29, 1966 K. LOEWENFELD DELIVERY SYSTEM FOR LOOSELY COHERENT SHEETS Filed Nov. 2, 1964 6 Sheets$heet 1 INVENTOR.

Kurf Loewenfeld Nov. 29, 1966 K. LOEWENFELD 3,288,057

DELIVERY SYSTEM FOR LOOSELY COHERENT SHEETS Filed Nov. 2, 1964 6 Sheets-Sheet 2 Kurf Loewenfe/d INVENTOR.

1966 K. 'LOEWENFELD 3,288,057

DELIVERY SYSTEM FOR LOOSELY COHERENT SHEETS Filed NOV. 2, 1964 6 Sheets-Sheet 3 Kurt Loewanfclc/ F i g 3 d INVENTOR.

AGENT Nov. 29, 1966 K. LOEWENFELD 3,288,057

DELIVERY SYSTEM FOR LOOSELY COHERENT SHEETS Filed Nov. 2, 1964 6 Sheets-Sheet 4 Kurf Loewenfe/d INVEN TOR.

AQENI Nov. 29, 1966 K. LOEWENFELD 3,288,057

DELIVERY SYSTEM FOR LOOSELY COHERENT SHEETS Filed Nov. 2, 1964 6 sheets-sheet 5 Z UH L %s (W I l, z s "h I In [CD 1 Kurf Loewenfeld INVENTOR.

Nov. 29, 1966 Filed Nov. 2, 1964 K LOEWENFELD DELIVERY SYSTEM FOR LOOSELY COHERENT SHEETS 6 Sheets-Shet 6 Fig 7 Kurf Loewenfeld INVENTOR.

AGENT United States Patent Q 8 Claims. (Cl. 100198) My present invention relates to a system for delivering sheets of loosely coherent material, such as so-called fiberboard sheets in their preformed state, to a press for final compacting. Systems of this general type have been described in commonly assigned US. Patents Nos. 3,050,200 and 3,077,271 issued August 21, 1962, and February 12, 1963, to E. Siempelkamp.

In prior systems of this type, such as those disclosed in the aforementioned patents, special means such as swingable chutes had to be provided for the purpose of removing the preformed sheets from their original transporter and distributing them onto a stack of endless bands which were moved by a common loading rack into the press, the bands being withdrawn from the press platen at the speed of their own rotation so that the sheets were deposited on the platens with only negligible stress in the direction of band motion. The chutes, however, were effective only for sheets of relatively restricted dimensions in the direction of advance; sheets of larger size in said direction, e.g. rectangular sheets placed lengthwise on the transporter, cannot be conveniently handled in that way and suffer objectionable strains on being alternately accelerated and slowed down in traveling from one conveyor to the other. Moreover, such sheets of greater length cannot be safely pushed off a stationary supporting surface (e.g. a tray) in longitudinal direction since the movement of the sheet is opposed by a large frictional resistance, proportional to the sheet length, so that the sheet is subject to deformation and may rupture.

The general object of my present invention is to provide an improved delivery system for transferring such sheets from a primary transporter, which may itself be an endless conveyor, onto a secondary conveyor arrangement formed at least in part by the aforementioned endless bands which serve in the manner already known to deposit the sheets on respective press platens. More particularly, it is an object of my invention to eliminate in such system the need for swingable chutes and to replace them by a transfer mechanism adapted safely to move even long rectangular sheets from the primary transporter onto the secondary conveyor arrangement.

This object is realized, in accordance with my present invention, by the provision of transfer means engageable with a sheet edge parallel to the path of the secondary conveyor, advantageously the longitudinal edge of the sheet, for displacing the sheet onto the endless band either directly or with the aid of an intermediate conveyor (e.g. an intermediate tray and/or band) by movement transverse to the supporting surface of the primary transporter.

The primary conveyor or other transporter may pass, in the manner described in the aforementioned patents,

underneath a spreader for the deposition of loose (e.g.

goes into operation at a location beyond the rough-formrng press, the frame is lifted by magnetic or other means off the supporting surface so as to expose the lateral edges of the sheet to be transferred.

The relative transverse motion between the sheet and the supporting surface of the primary transporter may be brought about either by a displacement of the sheet across the stationary surface or by a withdrawal of said surface underneath the stationary sheet. In either case the sheet will gradually come to rest, at a level just below that of the supporting surface of the primary transporter, on another supporting surface which may be that of a secondary conveyor or of an intermediate plate or tray; in the latter instance the transfer from the intermediate plate to the secondary conveyor takes place by relative transverse motion in the same manner as before and advantageously under the control of the same transfer mechanism.

The secondary conveyor either constitutes one of the endless bands of an elevatable loading'rack, such as the one described in the patents identified above, or cooperates with these bands to position successive sheets on different levels of a stack to be introduced into the spaces between the platens of the final press. The further treatment of the sheets proceeds in the well-known manner.

The invention will be described in greater detail with reference to the accompanying drawing in which:

FIG. 1 is a somewhat diagrammatical top plan view of a delivery system embodying the invention;

FIG. 2 is an elevational view taken on the line IIII of FIG. 1;

FIGS. 3a to 3d are cross-sectional views taken on the line III-III of FIG. 1, illustrating a succession of steps in the operation of a transfer mechanism forming part of the system of FIGS. 1 and 2;

FIGS. 4a to 40 are fragmentary elevational views taken on the line IV-IV of FIG. 1 and showing successive steps in the delivery of sheets from the transfer mechanism of FIGS. 3a to 3d to a final press;

FIGS. 5a and 5b are views similar to those of FIGS. 4a to 40, illustrating a modification;

FIG. 6 is an elevational view, similar to FIG. 2, of a further system according to my invention; and

FIG. 7 is a top plan view of the system illustrated in FIG. 6.

In FIGS. 1 and 2 I have shown a system for the mass production of fiberboard sheets by fully automatic means, this system being divided into two mirror-symmetrically arranged halves of which only one needs to be described in detail. This part of the system comprises a conveyor belt 10 that is guided around rollers 12, 13 and driven in termittently by a motor in the direction indicated by the arrows. The upper run of belt 10 is supported by a table 14 and passes underneath a spreader 15 and a preforming press 16, the former serving to deposit a fibrous mass 17 on the upper belt surface within the confines of a frame 18 in which this mass is subsequently flattened by the piston of press 16. Frame 18 is shown provided with locator pins 19 receivable in tapering bores 20 of the piston face of press 16 to insure proper positioning of the frame during the precompressing step. i

A lifting mechanism 21 beyond press 16 comprises a horizontal ram 22, rigid with the piston of a hydraulic or pneumatic cylinder 23, which terminates in a crossbar 24 riding on two horizontal rails 25. Bar 24 sup ports a pair of solenoids 26 whose armatures are fixed to an electromagnet 27 having an energizing winding 28. Magnet 27, which is thus lifted by the solenoids 26, serves to pick up the frame 18, the latter being made of a ferromagnetic material and normally resting loosely on belt 10 except for the slight residual magnetism which helps it retain its position thereon when the belt is preferentially constituted by a steel bar. The pole faces of magnet 27 are also conically recessed to accommodate the cator pins 19 of the frame.

When the cylinder 23 has aligned the bar 24 and magnet 27 with the frame 18 of a sheet 28 just produced by the press 16, as illustrated in dot-dash lines in FIG. 1, frame 18 is lifted off the belt surface to a higher level at which it is subsequently transported by the ram 22 to a location above another conveyor belt 10' running in the opposite direction. Belt 10' forms part of the second half of the system shown in FIG. 1 and moves below a spreader and a preforming press 16' which operate in the same manner as their counterparts 15 and 16. A further lifting mechanism 21', identical with mechanism 21, picks up the frame on belt 10 and returns it to belt 10 at a location just ahead of spreader 15. It will be seen that each frame 18 (six of which are used in system shown in FIG. 1) moves in a complete cycle, the intermittent motion of the two belts 10, 10' being synchronized with the operation of the lifting mechanisms 21 and 21' in such a manner that the transfer of frames between the two belts, occurring simultaneously in opposite directions, takes place concurrently with the deposit-ion of a pile of material 17 by the spreaders 15, 15 and with the flattening of another pile, formed in the cycle immediately preceding, by the presses 16 and 16' to produce preformed sheets 28, 28'.

Following the removal of its frame 18, the sheet 28 on belt 10 is advanced into a final position in line with a transfer mechanism generally designated 29. This mechanism, as best seen in FIGS. 3a to 3d, comprises a fluid cylinder 30 whose ram 31 carries a pusher bar32 engageable with the proximal longitudinal edge of the sheet. A receiving plate 33, secured to rams 34 of twin fluid cylinder 35, is horizontally displaceable by these rams on the level of the upper run of conveyor belt 10 and passes underneath a stationary stripper bar 36 secured to the base (not shown) of the machine. Another conveyor 37, supported by rollers 38', 38 as shown in FIGS. 4a to 40, is

disposed just below the level of plate 33 at a location just to the left of stripper bar 26 as viewed in FIGS. 30 to 3d.

The several views of FIGS. 3a to 3d show successive steps in the operation of transfer mechanism 29. In FIG. 3a the sheet 28 has come to rest on conveyor 10 alongside pusher bar 32 which has just been moved into contact with the left-hand edge of the sheet, this being one of the major sides of its rectangular outline. FIG. 3b shows the advance of bar 32 as it pushes sheet 28 onto the receiving plate 33 adjacent belt 10. In FIG. 30 the bar 32 has been retracted and the plate 33 has been moved toward the stripper bar 36 which acts as a stop for the sheet 28 so that the latter is gradually deposited upon the underlying belt 37. In FIG, 3d the transfer has been completed and sheet 28 rests fully on belt 37 which has remained stationary during this entire cycle.

As further shown in FIGS. 4a to 46, a rack 39 carrying a stack of endless conveyor belts 40 is disposed adjacent conveyor belt 37 between the later and a multiplaten press 41; an identical arrangement (transfer mechanism 29, rack 39' and press 41') is provided for the sheets 28' arriving over belt 10'. As more clearly shown in FIGS. 4a to 40, rack 39 is carried on a base 42 which is movable via rollers 43 in track-forming grooves on an elevatable platform 44 supported in turn by a hydraulically or pneumatically operated ram 45. Press 41, as illustrated schematically in FIGS. 4a to 46, comprises an upper and a lower bed plate 46, 47 as well as a set of 4 yond the platens 48 to receive the finished boards 28a therefrom.

The several views, FIGS. 4a to 4c, illustrate the mode of operation of the conveyor arrangement 37, 40 in loading the press 41. -In FIG. 4a the intermediate conveyor 37, having received a sheet 28 from the transfer mechanism 29 of FIGS. 3a to 3d, has been set in motion for advancing this sheet onto one of the endless bands 40 of rack 39, here the middle one of the three ilustrated bands; the conveyors 37 and 40 are moving in the same direction and at like speed to prevent any straining of the sheet 28. This operation is repeated on successive sheets, with intervening vertical movement of rack 39 to align successive bands 40 with conveyor 37 until all three bands have been loaded. This is illustrated in FIG. 4b where the three loaded bands 40, arrested once more, have been moved partly into the press 41 by a suitable drive mechanism D which advances the rack 39 horizontally across platform 34, the leading edges of the stationary belts 40 serving at the same time to dislodge the previously completed boards 28a from the press 41 and onto the rollers 49. These rollers may be driven or may lie on a slightly sloping plane in order to continue the movement of the finished boards away from the press. As illustrated in FIG. 4c, the sheets 28 are being deposited on the platens 48 by a withdrawal of rack 39 toward the right and a concurrent rotation of the belts 40 in a counter-clockwise direction, the linear speed of the belts equaling the rate of withdraw-a1 of rack 39 so that again the transfer of the sheets from one supporting surface to another proceeds with a minimum of stress. Following the complete withdrawal of the rack 39, into the position illustrated in FIG. 4a, press 41 is closed; though in FIG. 4a the press has been shown open for the sake of clarity, it will be understood that final compression and curing of the sheets may take place during the loading of the rack 39 as previously described.

In FIGS. 5a and 5b I have illustrated a modified rack 139 whose belts 140 are longer than the bands 40 of rack 39 and are themselves positionable directly below the plate 33 of FIGS. 3a to 3d so as to eliminate the need for an intermediate conveyor 37. The plate 33 may be withdrawn in this case completely beyond the belts 140 so as not to interfere with the vertical motion of the elevatable,

rack 39. FIG. 5a shows how a sheet on the uppermost belt 140 has been moved into proximity with the press 41 while another sheet is just being deposited on the middle belt; FIG. 5b shows all three belts loaded and ready to deliver their respective sheets 28 to the press.

In FIGS. 6 and 7 I have illustrated a considerably simplified system designed for reduced production rates.

The primary transporter is here constituted by a tray which is horizontally reciprocable on a base 114 by the rams 134 of twin fluid cylinders 135. The path of tray 110 passes again underneath a spreader, here designated 115, and a preforming press here indicated at 116, there being also provided a lifting mechanism 121 which is a simplified version of mechanism 21 and comprises a pair of electromagnets 127 supported by the ram 122 of a vertical cylinder 123. A yoke 150 disposed immediately above the path oftray 110 just ahead of spreader serves as an abutment for a frame 118 freely supported on said tray (except for the effect of residual magnetism as previously discussed); the presence of this yoke insuring that the frame 118 is always properly positioned on the tray 110 after the latter has been completely withdrawn toward the left; the yoke, of course, also establishes the proper position of the frame with respect to the tray as it proceeds to the press. Thus, the locator pins 19 of frame 18 may here be omitted.

A transfer mechanism 129 comprises a stop bar 136 which is vertically movable by twin cylinders 130 and rams 131 in order to descend upon the surface of tray 110 after the latter has been positioned above the secondary conveyor 137; it will be understood that, as described in conjunction with FIGS. 5a and 5b, this secondary conveyor may be replaced by one of the endless belts 140 of rack 139.

The system of FIGS. 6 and 7, using only a single frame 118, has an operating cycle in which mechanism 121 initially deposits this frame on the tray 110 aligned with it, the tray being subsequently withdrawn (dot-dash lines in FIG. 6) underneath the spreader 115 which fills the frame 118 with fibrous mass. Next, the tray 110 advances into a position below press 116 which descends to compact the mass within frame 118. Thereafter tray 110 steps once more under the lifter 121 which picks up the frame 118, the tray then moving past the bar 126 which at this time is held in its elevated position indicated in dot-dash lines. Subsequently, bar 136 is lowered to arrest the sheet 128 by engaging one of its major edges, tray 110 being concurrently withdrawn so that the sheet drops onto conveyor 137 whereupon the cycle is repeated. The further sheet-feeding operation proceeds in the manner already described.

The piston of the preforming press 16 or 116 could be designed with a recessed underside, as shown in the aforementioned U.S. patents, if the frames 18, 118 and the associated lifting mechanisms 21, 121 were omitted; the presence of such frames, however, insures accurate dimensioning of the preformed sheets 28 or 128. Naturally, the lifting mechanism could also operate by other than electromagnetic means and the entire system may be further modified in regardto its structural detail without departing from the spirit and scope of my invention as defined in the appended claims.

I claim: 1. A system for advancing substantially rectangular sheets of loosely coherent material toward a press having a platen and adapted to consolidate said sheets into rigid boards, comprising:

transport means forming a supporting surface for carrying a loosely coherent sheet along a predetermined path;

conveyor means disposed adjacent said path for receiving said sheet from said supporting surface;

transfer means engageable with an edge of said sheet for displacing said sheet onto said conveyor means by transverse movement relative to said supporting surface and a movable cairier provided with an endless band parallel to said edge forming part of said conveyor means and shiftable into a position overlying said platen for delivering said sheet to said press platen by a positioning of said band above said platen and subsequent unloading of said sheet fiom said band with concurrent withdrawal of said carrier at a speed substantially equaling the band speed.

2. A system for advancing substantially rectangular sheets of loosely coherent material toward a press having a platen and adapted to consolidate said sheets into rigid boards, comprising:

transport means forming a supporting surface for carrying a loosely coherent sheet along a predetermined path; conveyor means disposed adjacent said path for receiving said sheet from said supporting surface;

transfer means engageable with an edge of said sheet for displacing said sheet onto said conveyor means by transverse movement relative to said supporting surface;

and a movable carrier provided with an endless band parallel to said edge forming part of said conveyor means and shiftable into a position overlying said platen for delivering said sheet to said press platen by a positioning of said band above said platen and subsequent unloading of said sheet from said band with concurrent withdrawal of said carrier at a speed substantially equaling the band speed, said transfer means comprising a movable pusher member engageable with said edge, a horizontal plate positionable adjacent said transport means substantially at the level of said supporting surface for receiving said sheet therefrom, stop means immediately above said level, and mechanism for operating said pusher member to move said sheet onto said plate and subsequently displacing said plate past said stop means whereby the latter prevents said sheet from following said plate, said conveyor means including a band disposed immediately below said level adjacent said stop means.

3. A system for advancing substantially rectangular sheets of loosely coherent material toward a press having a platen and adapted to consolidate said sheets into rigid boards, comprising:

transport means forming a supporting surface for carrying a loosely coherent sheet along a predetermined path; conveyor means disposed adjacent said path for receiving said sheet from said supporting surface;

transfer means engageable with an edge of said sheet for displacing said sheet onto said conveyor means by transverse movement relative to said supporting surface;

and a movable carrier provided with an endless band parallel to said edge forming part of said conveyor means and shiftable into a position overlying said platen for delivering said sheet to said press platen by a positioning of said band above said platen and subsequent unloading of said sheet from said band with concurrent withdrawal of said carrier at a speed substantially equaling the band speed, said transfer means comprising a stop member positionable immediately above said supporting surface alongside said edge for preventing said sheet from following said supporting surface upon displacement thereof past said stop member, said conveyor means including a band disposed immediately below the level of said supporting surface adjacent said stop means.

4. A system for advancing substantially rectangular sheets of loosely coherent material toward a press having a platen and adapted to consolidate said sheets into rigid boards, comprising:

a frame for retaining loosely coherent material;

transport means forming a supporting surface for carrying a loosely coherent sheet together with a respective surrounding frame along a predetermined path; conveyor means disposed adjacent said path for receiving said sheet from said supporting surface; lifting means disposed along said path for removing said frame from said supporting surface; transfer means engageable with an edge of said sheet upon removal of said frame for displacing said sheet onto said conveyor means by transverse movement relative to said supporting surface;

and a movable carrier provided with an endless band parallel to said edge forming part of said conveyor means and shiftable into a position overlying said platen for delivering said sheet to said press platen by a positioning of said band above said platen and subsequent unloading of said sheet from said band with concurrent withdrawal of said carrier at a speed substantially equaling the band speed.

5. A system as defined in claim 4, further comprising spreader means above said path for depositing a mass of loose fibers on said supporting surface within said frame, and preforming means above said path adapted to produce said sheet by compacting said mass within said frame, said transport means being intermittently operable to advance said frame from said spreader means past said preforming means and said lifting means to said transfer means.

6. A system as defined in claim 5 wherein said transport means comprises an endless conveyor member successively movable past a first location ahead of said spreader means, a second location below said spreader means, a

third location below said preforming means, a fourth location beyond said preforming means and a fifth location adjacent said transfer means, said lifting means being operable to remove said frame from said member at said fourth location and to return it to said member at said first location.

7. A system as defined in claim 6 wherein said lifting means includes another endless conveyor member movable in a direction opposite that of the first-mentioned conveyor member.

8. A system for advancing substantially rectangular sheets of loosely coherent material toward a press adapted to consolidate said sheets into rigid boards, comprising:

a frame for retaining loosely coherent material; transport means forming a supporting surface for carrying a loosely coherent sheet together with a respective surrounding frame along a predetermined path;

conveyor means disposed adjacent said path for receiving said sheet from said supporting surface,

lifting means disposed along said path for removing said frame from said supporting surface;

transfer means engageable with an edge of said sheet parallel to said path upon removal of said frame for displacing said sheet onto said conveyor means by transverse movement relative to said supportnig surface;

and a movable carrier provided with an elevatable rack, said conveyor means including a stack of endsequent unloading of said sheetsfrom said bands with concurrent withdrawal of said carrier and rack at a speed substantially equaling the band speed.

References Cited by the Examiner UNITED STATES PATENTS 2,017,535 10/1935 Hammer 2l4l6.6 2,728,468 12/ 1955 Siempelkamp. 2,989,774 6/ 1961 Erickson et al. 18-4 X 3,050,200 8/ 1962 Siempelkamp 214-16.6 3,077,271 2/ 1963 Siempelkamp 214l6.6

FOREIGN PATENTS 1,311,915 11/1962 France.

356,874 9/193 1 Great Britain.

655,952 8/1951 Great Britain.

858,412 1/1961 Great Britain.

WALTER A. SCHEEL, Primary Examiner.

B. I. WILHITE, Examiner. 

1. A SYSTEM FOR ADVANCING SUBSTANTIALLY RECTANGULAR SHEETS OF LOOSELY COHERENT MATERIAL TOWARD A PRESS HAVING A PLATEN AND ADAPTED TO CONDOLIDATE SAID SHEET INTO RIGID BOARDS, COMPRISING: TRANSPORT MEANS FORMING A SUPPORTING SURFACE FOR CARRYING A LOOSELY COHERENT SHEET ALONG A PREDETERMINED PATH; CONVEYOR MEANS DISPOSED ADJACENT SAID PATH FOR RECEIVING SAID SHEET FORMING SAID SUPPORTING SURFACE; TRANSFER MEANS ENGAGEABLE WITH AN EDGE OF SAID SHEET FOR DISPLACING SAID SHEET ONTO SAID CONVEYOR MEANS BY TRANSVERSE MOVEMENT RELATIVE TO SAID SUPPORTING SURFACE; AND A MOVABLE CARRIER PROVIDED WITH AN ENDLESS BAND PARALLEL TO SAID EDGE FORMING PART OF SAID CONVEYOR MEANS AND SHIFTABLE INTO A POSITION OVERLYING SAID PLATEN FOR DELIVERING SAID SHEET TO SAID PRESS PLATEN BY A POSITIONING OF SAID BAND ABOVE SAID PLATEN AND SUBSEQUENT UNLOADING OF SAID SHEET FROM SAID BAND WITH CONCUTTENT WITHDRAWAL OF SAID CARRIER AT A SPEED SUBSTANTIALLY EQUALING THE BAND SPEED. 